overheating issues - 79 k10

[Stepside Man]

I am a former radiator mechanic.

Did you use silicone anywhere in the building process? That can travel through an engine and end up in weird spots. Seen it many times.

Try running the truck with the thermostat complete out of it. You may have a stuck shut thermostat.

Air binding is usually not a problem with these trucks. As long as you have original style radiator. The high point in the system is the radiator.

Glowing manifolds is very much a problem. You have a restriction in the exhaust somewhere. You should be running dual exhaust anyway.

Are you using a clutch fan? Looks good at idle but clutch may be bad and fan not really working while you are running. This was a common issue for my customers.

Check to make sure you dont have a 2 core straight six radiator. 3 core min.

Remember just because a part is new doesnt mean that it is working correctly.

[tommartin]

Originally Posted by wilkin250r

Ignition timing can be a funny thing. Too much advance can cause heat buildup, but it's usually a slow buildup and doesn't result in glowing exhaust pipes. Retarded timing, if severe, can cause glowing exhaust pipes because the spark is so late that the fuel is still burning as it exits the combustion chamber into the exhaust. Retarded timing can also cause overheating (I know, odd that both advanced and retarded timing can cause overheating) because as the burning exhaust exits the combustion chamber, it passes a lot of heat into the cylinder heat.

A lean fuel/air mixture will cause overheating and glowing exhaust pipes.

And keep in mind, you might actually have SEVERAL issues. You might have a lean mixture AND a water flow problem, and they both manifest as an overheating issue.

My advice would be to deal with the glowing exhaust first, and check all possibilities there. That's still a problem even if your cooling system was working perfectly fine.

Ok, guys i know this was from a few months back, but I did want to let you know it was timing issue.

I’m not a timing expert at all, I just adjusted my distributor and it sounded good, so I left it and sure enough it stopped overheating.

Thanks for the help.